53 research outputs found
The differences between Paphiopedilum barbatum (Lindl.) and Papiopedilum callosum (Rchb.f.) Stein var. sublaeve (Rchb.f.) P.J. Cribb
The genus Paphiopedilum is a flagship species among orchids and comprises of some of the most sought after orchids for its beauty and rarity. Thus, all Paphiopedilum are placed in CITES Appendix I. Among orchids, Paphiopedilum has the most revised literature. In spite of this, misidentifications tend to occur even in publications. This is mainly due to the close resemblance that some species have with each other. Identification is important for the accurate knowledge on the distribution of the species done through biodiversity inventories as this can result in the decision making of environmental policies and conservation strategies. In the case of P. barbatum and P. callosum var. sublaeve, methods used for the correct species identification include morphological study, distribution and DNA barcoding. The morphology presents many similarities between both species but with some differences in the petal angle, staminode shape and the presence of ciliated hair on the petal margins. Distributions of both species in Peninsular Malaysia do not overlap. DNA barcoding using the molecular markers; rbcL, matK and ITS, were used to differentiate both species. Analysis of sequences generated shows ITS and matK forming two separate clades for each species in Neighbour-Joining trees. The rbcL sequences provided poor species resolution as evidenced from the formation of multiple clades for both species. Presence of barcoding gap and BLAST results were used to confirm the two species. DNA barcoding is an effective taxonomic tool and accuracy is increased when morphology and distribution data are included
Isolation, cloning, and sub-cellular localization of transketolase from Amaranthus tricolor L.
Transketolase (TK) is one of the key enzymes that involved in the Oxidative Pentose Phosphate Pathway (OPPP), and produce erythrose-4-phosphate which is the precursor for many secondary metabolites such as aromatic amino acids, lignin and flavonoid. The OPPP is composed of two functionally-connected phases, the oxidative and non-oxidative phase. The complete OPPP is localized in cytosol of animal and prokaryotic. However, in plant, the first phase is localised in cytosol but the sub-cellular localization of the second phase of OPPP is still under debate. There is no study available on transketolase in Amaranthus tricolor till to day? Therefore, the objectives of study are to isolate TK gene from Amaranthus tricolor, to compare its identity with other plant species and to determine its sub-cellular localization. The full length of 2021bp nucleotide sequence of TK had been isolated from A. tricolor by RT-PCR. ClustalW revealed that A. tricolor TK sequences showed high similarity (more than 81 %) within plants’ other species. Subcellular localization by using TargetP 1.1 and ChloroP revealed that of A. tricolor TK was located in the plastid. Thus it can be concluded that the OPPP is incomplete in the cytosol
A glimpse into the genomic outlook of the long-tailed macaque (Macaca fascicularis)
The long-tailed macaque (Macaca fascicularis) is commonly used for biomedical researches. However, genetic variation within a population or among populations can significantly affect phenotypical outcomes of treatments tested on model organisms. As such, it is important for studies involving model organisms originating from different, or even the same geographical locations to have sufficient genomic and transcriptomic background of the model organisms that is used. This paper summarises the utilisation of next-generation sequencing (NGS) technology to sequence genomes and transcriptomes of long-tailed macaques from various geographical populations in general and the Malaysian long-tailed macaque in particular, and its importance in the context of population genetic studies
Isolation and characterization of full-length cellulose synthase gene (HsCesA1) from Roselle (Hibiscus sabdariffa L. var. UMKL)
The Hibiscus sabdariffa var. UMKL (Roselle) investigated here may potentially be used as an alternative fibre source. To the best of our knowledge, there was no study focusing on the genetics underlying the cellulose biosynthesis machinery in Roselle thus far. This paper presents the results of the first isolation of the cellulose synthase gene, HsCesA1 from this plant, which is fundamental for working towards understanding the functions of CesA genes in the cellulose biosynthesis of Roselle. A full-length HsCesA1 cDNA of 3528 bp in length (accession no: KJ608192) encoding a polypeptide of 974 amino acid was isolated. The full-length HsCesA1 gene of 5489 bp length (accession no: KJ661223) with 11-introns and a promoter region of 737 bp was further isolated. Important and conserved characteristics of a CesA protein were identified in the HsCesA1 deduced amino acid sequence, which strengthened the prediction that the isolated gene being a cellulose synthase belonging to the processive class of the 2-glycosyltransferase family 2A. Relative gene expression analysis by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) on young leaf and stem tissues found that HsCesA1 had similar levels of gene expression in both tissues. Phylogenetic and Blast analyses also supported the prediction that the isolated HsCesA1 may play roles in the cell wall depositions in both leaf and stem tissues
Morphometric sexing of little spiderhunter (Arachnothera longirostra) in Peninsular Malaysia
Sexual dimorphism is often directly linked to sexual selection, mating systems and resource partitioning, which are crucial in species conservation and management. Many avian species, including pollinator birds, are sexually dimorphic with respect to size and colour, yet, such differences may be subtle for some species. In this study, molecular sexing was performed in addition to determining morphological parameters that can aid in future sex determination of a common forest pollinator, the little spiderhunter (Arachnothera longirostra), in Peninsular Malaysia. Based on 23 captures made in four forests, two out of seven body measurements (i.e. wing and tail lengths) were useful in predicting the sexes of the bird with 100% accuracy. In addition, significant differences were found in the head, bill, and total body lengths. Such findings will facilitate more effective sex identification in future field studies, particularly in the case of juveniles
Uptake of Mn and Cd by wild water spinach and their bioaccumulation and translocation factors
Polluted ponds and lakes close to agricultural activities become the exposure route of manganese (Mn) and cadmium (Cd) to aquatic plants in near vicinity. Therefore, a study of the uptake, bioaccumulation, and translocation of Mn and Cd by the water spinach (Ipomoea aquatica) is presented in this paper. Different concentrations of Mn and Cd were added to the hydroponic nutrient solution that was used to grow the plants for the heavy metal uptake experiment under greenhouse conditions. The plant samples exposed to heavy metals were collected to determine the metal concentrations using atomic absorption spectroscopy (AAS) and the metal concentrations were found for Mn was between 1.589 to 9.696 µg/g and Cd from 5.309 to 10.947 µg/g. The correlation and regression results showed that the water-to-shoot bioaccumulation factor (BAF) decreased for Mn, while root-to-shoot translocation factor (TF) values increased in the order Cd > Mn to the increasing levels of metals in the water. Furthermore, it was revealed from the two-way analysis of variance (ANOVA) that the different metal types influenced the BAF and TF values at different metal concentration treatments
Development of species-specific SCAR markers for identification and authentication of three rare Peninsular Malaysian endemic Coelogyne (Orchidaceae) orchids
Background: Coelogyne kaliana, Coelogyne stenochila and Coelogyne tiomanensis are three valuable rare orchid species endemic to Peninsular Malaysia, currently rampantly traded illegally via the internet and through local nurseries, which label them as hybrids to avoid enforcement detection. Drastic measures to ensure the continued existence of their populations in the wild should be introduced as they are rapidly diminishing into extinction, including the development of rapid and accurate species-specific identification tools. These three orchid species are highly similar morphologically and currently it is impossible to distinguish among them without their reproductive structures. Methods: RAPD-based species-specific SCAR markers were developed to distinguish and authenticate the identity of these three endemic Peninsular Malaysian Coelogyne species. Results: Three SCAR markers were successfully developed in this study. SCAR marker primer pair , CKL_f / CKL_r was specific to C. kaliana as it produced a unique single band of 271 bp but not in C. stenochila and C. tiomanensis. SCAR marker primer pair CST_f / CST_r amplified a single band of 854 bp in C. stenochila and two bands of different sizes (372 bp and 858 bp) in C. tiomanensis, but no amplification in C. kaliana. The third SCAR marker primer pair, CTI_f / CTI_r produced a single band (about 500 bp) for both C. stenochila and C. tiomanensis, but showed no amplification in C. kaliana. Conclusions: Although not all these SCAR markers were species amplification specific, they could be used to discriminate among the three Coelogyne species effectively. Accurate species identification is one of the most important steps to allow a proper management plan to be established in the effort to conserve these three endangered orchid species of Peninsular Malaysia. Besides, it could effectively put a stop to the illegal trading of these rare endangered orchid species worldwide
DNA barcoding of endangered Paphiopedilum species (Orchidaceae) of Peninsular Malaysia
In this study, the efficacy of four DNA markers and their combinations (rbcL, matK, ITS, trnH-psbA) as barcode markers were tested across the endangered Paphiopedilum species from Peninsular Malaysia. Four species of Paphiopedilum were sampled and barcoded. The DNA barcodes reliabilities were evaluated using NCBI BLASTn program, phylogenetic tree via Neighbour-Joining method with 1000 bootstrap replicates in MEGA 6 and barcoding gap assessment. matK is the most promising barcode with high sequence quality (100%), high accuracy in BLASTn (100%), clear resolution of species in Neighbour-Joining phylogenetic tree (100%) and a distinct barcoding gap followed by ITS, trnH-psbA and rbcL. The combination of barcode regions revealed the lack of variation in rbcL and trnH-psbA but they are still useful for preliminary identification followed up by matK for accurate identification
Efficacy of KNO3, SiO2 and SA priming for improving emergence, seedling growth and antioxidant enzymes of rice (Oryza sativa), under drought
Rice is an important staple crop produced and consumed worldwide. However, poor seed emergence is one of the main impediments to obtaining higher yield of rice especially in hot and dry ecosystems of the world that are ravaged by drought. Therefore, this study was carried out to evaluate the effects of potassium nitrate (KNO3), salicylic acid (SA) and silicon dioxide (SiO2) priming in improving emergence, seedling growth, biochemical attributes and antioxidant activities of FARO44 rice under drought conditions. Rice seedlings primed with 2.5% and 5% KNO3, 3% and 3.5% SiO2, and 1 mM and 2.5 mM SA were subjected to three drought levels of low, moderate and severe under the greenhouse. Seed emergence, seedling growth, biochemical attributes and antioxidant activities were thereafter evaluated. Seed priming experiments were laid in a completely randomized design with five replicates per treatment. The results found that rice seedlings responded differently to different priming treatments. However, all primed rice seedlings had significantly (P ≤ 0.05) improved emergence percentage (72–92%), seedling growth, seedling vigor, seedling fresh and dry biomass and shorter emergence time compared with controls. Likewise, total soluble protein content, activities of catalase, ascorbate peroxidase and superoxide dismutase, carbohydrate, soluble sugar and total chlorophyll contents of rice seedlings were increased by more than two-folds by seed priming compared with control. Salicylic acid showed less effect in increasing emergence, seedling growth, antioxidant activities and biochemical attributes of rice. Thus, this study established that seed priming with KNO3 (2.5% and 5%) and SiO2 (3% and 3.5%) were more effective in improving emergence, seedling growth, biochemical attributes and antioxidant activities of FARO44. Thus, priming of FARO44 rice with this chemical is recommended for fast emergence, seedling growth and drought resistance in dry ecosystems
Vinca alkaloids
Vinca alkaloids are a subset of drugs obtained from the
Madagascar periwinkle plant. They are naturally extracted from the pink periwinkle plant, Catharanthus roseus G. Don and have a hypoglycemic as well as cytotoxic effects. They have been used to treat diabetes, high blood pressure and have been used as disinfectants. The vinca alkaloids are also important for being cancer fighters. There are four major vinca alkaloids in clinical use: Vinblastine (VBL), vinorelbine (VRL), vincristine (VCR) and vindesine (VDS). VCR, VBL and VRL have been approved for use in the United States. Vinflunine is also a new synthetic vinca alkaloid, which has been approved in Europe for the treatment
of second‑line transitional cell carcinoma of the urothelium is being developed for other malignancies. Vinca alkaloids are the second‑most‑used class of cancer drugs and will stay among the original cancer therapies. Different researches and studies for new vinca alkaloid applications will be carried out in this regard
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